This invention relates to an optical sensor for the detection of gaseous air contaminants, especially acid vapors.
Chemical sensor technologies have been used increasingly for the detection or monitoring of hazardous vapors in the workplace environment. Applications include portable sensors or dosimeters to monitor individual personal exposure, or fixed-site sensors to monitor ambient concentrations of chemical species. The great attraction of these technologies is their capability for rapid, sensitive response at low cost.
It is an object of this invention to provide improved, portable, inexpensive, and selective chemical sensors for use in: protective equipment, such as gas masks, as an end-of-service alarm; dosimeters for monitoring individual exposure; or ambient air monitors.
It is a particular object of this invention to provide reliable sensors for the detection of acid vapors, such as vapors of HCl or H.sub.2 S.
It is another object of this invention to provide chemical sensors that use an optical waveguide which renders them substantially unsusceptible to electromagnetic interference.
It is yet another object of this invention to provide reliable sensors for the detection of basic vapors, such as vapors of ammonia, amines or hydrazines.